This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.

<=> 

        # Complex.<=>

(from ruby core)
---
    cmp <=> object  ->  0, 1, -1, or nil

---

If `cmp`'s imaginary part is zero, and `object` is also a real number
(or a Complex number where the imaginary part is zero), compare the real
part of `cmp` to object.  Otherwise, return nil.

    Complex(2, 3)  <=> Complex(2, 3)   #=> nil
    Complex(2, 3)  <=> 1               #=> nil
    Complex(2)     <=> 1               #=> 1
    Complex(2)     <=> 2               #=> 0
    Complex(2)     <=> 3               #=> -1

This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.